The present invention relates to a device for electronically controlling loom components such as, for instance but not exclusively, the components for inserting the woof.
The invention, in particular, relates to a device of the kind defined hereinabove essentially made up of a system of coding and programming means. A number of examples of execution of such systems are already known. They are generally composed of similar or equivalent programming means, but show clear, differences in the coding system.
For instance, in the Dutch patent application No. 7511121 is described a controlling device, characterized in that the coding is carried out on the crankshaft of the loom through electronic events. Now, the controlling devices that are particularly suited for equipping rapier looms, are not suited for equipping other looms, such as looms in which the insertion of the woof thread is being carried out pneumatically, through projection or by means of a shuttle.
The German patent application DAS No. 28 36 206 recommends use of purely mechanical code system, allowing the reading of angle degrees on the crankshaft. This solution, which as the preceding ones excellently suits the equipment of rapier looms, shows appreciable drawbacks in looms without mechanical coupling of the woof thread insertion component, such as are the looms with pneumatic insertion of the woof thread.
One of the great difficulties in the projection looms, and above all in the pneumatic looms, lies in the fact that the insertion of the woof thread into the opening of the warp depends on a number of factors which, on the whole, are independent of the angular position of the crankshaft, such as the reaction time of the valves, the pressure increase in the nozzles, etc.
The fact that the control of the nozzles in a pneumatic loom poses problems which are difficult to resolve is clearly illustrated by the great number of solutions recommended to date, i.e. the U.S. Pat. Nos. 3,705,608 and 3,821,972, the Dutch Pat. No. 7901050; and the English Pat. No. 1,470,752 etc.